From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757600AbbDVS4J (ORCPT ); Wed, 22 Apr 2015 14:56:09 -0400 Received: from mga11.intel.com ([192.55.52.93]:41284 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751928AbbDVS4G (ORCPT ); Wed, 22 Apr 2015 14:56:06 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.11,625,1422950400"; d="scan'208";a="560198974" From: Jarkko Sakkinen To: peterhuewe@gmx.de, tpmdd-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org Cc: Jarkko Sakkinen , Greg Kroah-Hartman , Tejun Heo , Andrew Morton , Al Viro , Jianyu Zhan , Rasmus Villemoes , "Eric W. Biederman" , Andrzej Hajda , Simon Wunderlich , NeilBrown , Guenter Roeck Subject: [PATCH v3 1/2] sysfs: added sysfs_link_entry_to_kobj() Date: Wed, 22 Apr 2015 21:54:16 +0300 Message-Id: <1429728857-6372-2-git-send-email-jarkko.sakkinen@linux.intel.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1429728857-6372-1-git-send-email-jarkko.sakkinen@linux.intel.com> References: <1429728857-6372-1-git-send-email-jarkko.sakkinen@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Added a new function sysfs_link_group_to_kobj() that adds a symlink from attribute or group to a kobject. Exported kernfs_remove_by_name_ns in order to provide a way to remove such symlinks. Signed-off-by: Jarkko Sakkinen --- fs/kernfs/dir.c | 1 + fs/sysfs/group.c | 42 ++++++++++++++++++++++++++++++++++++++++++ include/linux/sysfs.h | 8 ++++++++ 3 files changed, 51 insertions(+) diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c index 6acc964..749cea3 100644 --- a/fs/kernfs/dir.c +++ b/fs/kernfs/dir.c @@ -1225,6 +1225,7 @@ int kernfs_remove_by_name_ns(struct kernfs_node *parent, const char *name, else return -ENOENT; } +EXPORT_SYMBOL_GPL(kernfs_remove_by_name_ns); /** * kernfs_rename_ns - move and rename a kernfs_node diff --git a/fs/sysfs/group.c b/fs/sysfs/group.c index b400c04..5c72996 100644 --- a/fs/sysfs/group.c +++ b/fs/sysfs/group.c @@ -352,3 +352,45 @@ void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name, } } EXPORT_SYMBOL_GPL(sysfs_remove_link_from_group); + +/** + * sysfs_link_entry_to_kobj - add a symlink to a kobject pointing to a group or an attribute + * @kobj: The kobject containing the group. + * @target_kobj: The target kobject. + * @target_name: The name of the target group or attribute. + */ +int sysfs_link_entry_to_kobj(struct kobject *kobj, struct kobject *target_kobj, + const char *target_name) +{ + struct kernfs_node *target; + struct kernfs_node *entry; + struct kernfs_node *link; + + /* + * We don't own @target_kobj and it may be removed at any time. + * Synchronize using sysfs_symlink_target_lock. See sysfs_remove_dir() + * for details. + */ + spin_lock(&sysfs_symlink_target_lock); + target = target_kobj->sd; + if (target) + kernfs_get(target); + spin_unlock(&sysfs_symlink_target_lock); + if (!target) + return -ENOENT; + + entry = kernfs_find_and_get(target_kobj->sd, target_name); + if (!entry) { + kernfs_put(target); + return -ENOENT; + } + + link = kernfs_create_link(kobj->sd, target_name, entry); + if (IS_ERR(link) && PTR_ERR(link) == -EEXIST) + sysfs_warn_dup(kobj->sd, target_name); + + kernfs_put(entry); + kernfs_put(target); + return IS_ERR(link) ? PTR_ERR(link) : 0; +} +EXPORT_SYMBOL_GPL(sysfs_link_entry_to_kobj); diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index 99382c0..f2be044 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -264,6 +264,8 @@ int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name, struct kobject *target, const char *link_name); void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name, const char *link_name); +int sysfs_link_entry_to_kobj(struct kobject *kobj, struct kobject *target_kobj, + const char *target_name); void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr); @@ -436,6 +438,12 @@ static inline void sysfs_remove_link_from_group(struct kobject *kobj, { } +int sysfs_link_entry_to_kobj(struct kobject *kobj, struct kobject *target_kobj, + const char *target_name) +{ + return 0; +} + static inline void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr) { -- 2.1.4